Port Forward Table (CXi, CXi II, MXe and MXe Server only)

Purpose:

The Port Forward Table form allows external traffic to reach resources on the internal network. The table can contain up to 40 entries. Each entry consists of a protocol (TCP or UDP) and port number combination on the Internet Gateway (WAN interface) as well as an IP address and port number combination on the internal network.

After an entry has been added to the table, a host on the internet can send a packet to the WAN interface for the specified protocol/port number combination. The firewall re-addresses the packet, sending it to the IP address/port number combination of the actual resource or service on the internal network.

Use this form when performing the following tasks:

Conditions

Field Descriptions

Parameter

Description

Default Value

Protocol

Select the WAN interface protocol (UDP or TCP).

TCP

Src Start Port

Enter the source port at start of the range. The source start port for a TCP entry must not overlap with other TCP entries, and the source start port for a UDP entry must not overlap with other UDP entries. The source start port must be less than or equal to the respective end port. Valid port numbers are 1-65535.

Blank

Src End Port

Enter the source port at end of the range. The source end port for a TCP entry must not overlap with other TCP entries. The source end port for a UDP entry must not overlap with other UDP entries. Valid port numbers are 1-65535.

Blank

Dst IP Address

Enter the IP address of the destination device that receives the specified packets.

Blank

Dst Start Port

Enter the destination port at start of the range.  The destination start port must be less than or equal to the respective end port. Valid port numbers are 1-65535. The default is blank.

  • Note: If the destination start port is omitted, it will automatically map to the source start port when the new table entry is saved.

Blank

Dst End Port

System-generated, protected field. Indicates the destination ports at end of the range. Valid port numbers are 1-65535.  The range of destination end ports match the range of source end ports. The default is blank.

  • Note: The system updates this field after you click Save.

 

Examples

Example 1:

Protocol

Src Port (Start/End)

Dst Port (Start/End)

TCP

10000/20000

10000/20000

TCP

30000/40000

30000/40000

UDP

20000/30000

20000/30000

UDP

40000/50000

40000/50000

 

In Example 2, the source ports are mapped to a different range of destination ports. In this case, it takes approximately 10 to 13 seconds to map each 1000 ports so it would take approximately 6 to 7 minutes for the configuration changes to take effect:

Example 2:

Protocol

Src Port (Start/End)

Dst Port (Start/End)

TCP

10000/20000

11000/21000

TCP

30000/40000

31000/41000

UDP

20000/30000

21000/31000

UDP

40000/50000

41000/51000

 

In Example 3, the range of ports that is being mapped is very large. In this case, it takes approximately 25 to 30 minutes for the configuration changes to take effect:

Example 3:

Protocol

Src Port (Start/End)

Dst Port (Start/End)

TCP

10000/30000

11000/31000

TCP

30000/50000

31000/51000

UDP

20000/40000

21000/41000

UDP

40000/60000

41000/61000